IRANDERMA

What is your diagnosis for this
45-year-old man? He referred for
evaluating a solitary tumor on his arm. The lesion was asymptomatic and
slowly enlarging since 6 months ago.
There was no history for any underlying disease and the patient was on no
medications.

It has been reported that
immunohistochemistry in
such lesions may be
positive for smooth
muscle actin and factor
VIII related antigen,
which are typically
negative in KS.

It has been shown that in such
cases the best way to
differentiate KS-like PG
from a true KS is to
test for the presence of
HHV-8 DNA using the
polymerase chain
reaction (PCR). In such
cases caution should be
taken not to diagnose
solely on the basis of
immunohistochemistry
phenotype.